Plant tissues and tissue system Flashcards
(14 cards)
– part of plant where cell division (mitosis) or production of new cells occurs.
- Meristematic tissue
– tip of stems and roots (shoot or root apical meristem) that give rise to primary meristem[under Meristematic tissue]
a. Apical meristem
– stem and roots
b1. Vascular cambium
b2. Phellogen (cork cambium) [under Meristematic tissue]
b. Lateral meristem
– internodes and bases of young leaves [under Meristematic tissue]
c. Intercallary meristem
– derived from meristems which have attained maturity form thus perform their specific function/s.
a. Epidermis
b. Parenchyma
c. Collenchyma
d. Sclerenchyma
e. cork
- Permanent tissue
- Outermost layer of cells of the primary plant body
- Contain stomata, trichomes (appendages)
A. EPIDERMIS [under Permanent Tissue]
- cortical regions of stems and roots and in the mesophyll of the leaves.
- storage and support to photosynthesis and phloem loading.
- Apart from the xylem and phloem in its vascular bundles, leaves are composed mainly of parenchyma cells.
- Some parenchyma cells, as in the epidermis, are specialized for light penetration and focusing or regulation of gas exchange.
B. PARENCHYMA [under Permanent Tissue]
- Thickened tissue found in the cortex of the stem and petioles or along the veins of the leaves
- Cells are alive at maturity and have only a primary wall.
- These cells mature from meristem derivatives that initially resemble parenchyma, but differences quickly become apparent.
C. COLLLENCHYMA [under Permanent Tissue]
- cells are hard and tough cells with a function in mechanical support.
- Scattered throughout the plant, found in both primary and secondary tissues.
D. SCLERENCHYMA [under Permanent Tissue]
TYPES OF SCLERENCHYMA
- known as bast fibers
- Long, thin cells with very thick walls often dead at maturity
– similar with fibers thick wall and lignified; may be living or dead at maturity.
a. Fibers
b. Scheroids or stone cells
- Outermost tissue; impregnated with suberin (waxy substance)
E. CORK
Complex Permanent Tissue/Types of vascular tissues
2 Main Types
Xylem
Phloem
- Distributes water and dissolved minerals UPWARD the plant body (from the roots to the leaves)
- Consist of tracheids, vessel membrane xylem fibers and xylem parenchyma
*tubular shaped structure with the absence of cross walls. This tissue resembles the shape of a star.
Xylem
- Carries food downward from the leaves to the roots.
- Distributes the dissolved food materials between the source and sinks
- Tubular-shaped, elongated, structures with the presence of walls with thin sieve tubes.
Phloem
